According to Dante, you'd have to do at least 10 hours a day for a week to counterbreak at 10k without catapults. Sure you can give the argument you don't need to counterbreak, but its a thing people do every war. It should be an expected variable cause its happened for years on end now.
I'm just gonna post my thoughts on this matter in general here.
With the game having the counterbreak AS A FEATURE, it's essentially the devs saying that they think this is a reasonable number for players to do. If there was no limit at all, it wouldn't be them encouraging anything, but as there is, well, here we are.
The issue with 10k is the time commitment needed. We've had 10k as the standard for a while now, and during that time, there have been both 1 week wars AND wars with only footwaves.
Now, given that wars are a community effort first and foremost, I think it makes sense to assume that the expectation is that you do your farming during the actual war, and not the post-war time.
While it's an extreme case, this means that in the worst case, you'd need to hit 10k waves in a week. At, say, 2.5WPM, that's 67ish hours. Adding even just 30 minute breaks, you're pretty much looking at 10 hours a day. You know what that's called? That's a *job*.
Given that MOST people have real life commitments that don't involve pressing buttons for hours on end, be it school, work or anything else, it's not a very reasonable expectation. (Mind that even in the more common two weeks scenario, it'd be 5 hours)
The way I see this, is that wars are actively promoting unhealthy gaming habits. You can say that it's the responsibility of a player to avoid that, but the game would do very well to at least not encourage that kind of behaviour.
I want to note that it seems Verly was not previously aware what an absurd grind the Defender gear was, and was willing to fix that, so I'm holding some hope on that front. (Mind that stuff like the Cannon remained as is because it's a long term goal for players that have done everything else in wars. This is fine, long term goals aren't nearly as much of an issue, but per war counters are a short term deal. you either do it NOW, or you lost your chance)
So, what could be done to fix this? Just lowering the counterbreak point would be fine, really. The mini war last time was a much more reasonable task. Now, of course, there are people who like being able to track their waves beyond that. There are some options for that, but the most simple (from a coding perspective of someone who doesn't know much about Flash nonsense) would just be to make a, say, a 1k DM merge item that can be sold for Gold or some such, that a player can easily use to keep track of their warring prowess, if they so wish. (Obviously they could do so via other DM items too)
@Surib, and then what, keep the mechanic in the Inn because it is, to your perspective, oppressive to the casual? Yes, it is in its prototypical stages, but you miss the point that it bypasses the need to walk a long ways about on the screen. Between trying to precisely target walk a mook scattered in a large room (and we've gotten those in previous wars) only to miss it and aggro another, I'd rather have this and end them in split seconds, with equal time spent to make sure my character's placement is spot on on the y-axis.
I think there's a few things here.
-DDR requires a higher level of focus, because misclicking is far more punishing now. Especially in the case of multi enemy waves on a class with one multi. This is pretty bad because wars are a grind-focused event, so most players tend to prefer the ability to pay as little attention as possible.
-DDR doesn't need to be Inn exclusive, but having it, especially, as you say, in a "prototypical stage" be an integral part of an event you want efficiency in is not the best. Having it in regular quests first would be preferable, this could (and is, based on some people having issues) be the first time players see this particular concept.
Now, not all is bad, because I don't think more options is a bad thing. If DDR in the future becomes an alternative way to farm, those that prefer DDR can have DDR. Interestingly, due to less optimization needed on the walkaround parts (well, none in this case), it may very well be a faster way to war for some people, at the cost of more focus. However, it does sort of hardcap your speed, which especially affects the higher-end players, the ones that are more likely to go for the high numbers.
The other way to lessen the impact might be to make it less punishing in that it doesn't mitigate all your damage, like HellsWolf666 suggested. More experienced players would probably take the time to optimize this too, to make sure mistakes are less costly to the best of their abilities.